<template>
    <div class="component-upload-image">
        <el-upload
            multiple
            :action="uploadImgUrl"
            list-type="picture-card"
            :on-success="handleUploadSuccess"
            :before-upload="handleBeforeUpload"
            :limit="limit"
            :on-error="handleUploadError"
            :on-exceed="handleExceed"
            ref="imageUpload"
            :before-remove="handleDelete"
            :show-file-list="true"
            :headers="headers"
            :file-list="fileList"
            :on-preview="handlePictureCardPreview"
            :class="{ hide: fileList.length >= limit }"
        >
            <el-icon class="avatar-uploader-icon"><plus /></el-icon>
        </el-upload>
        <!-- 上传提示 -->
        <div class="el-upload__tip" v-if="showTip">
            请上传
            <template v-if="fileSize">
                大小不超过 <b style="color: #f56c6c">{{ fileSize }}MB</b>
            </template>
            <template v-if="fileType">
                格式为 <b style="color: #f56c6c">{{ fileType.join('/') }}</b>
            </template>
            的文件
        </div>

        <el-dialog
            v-model="dialogVisible"
            title="预览"
            width="800px"
            append-to-body
        >
            <img
                :src="dialogImageUrl"
                style="display: block; max-width: 100%; margin: 0 auto"
            />
        </el-dialog>
    </div>
</template>

<script setup>
import { getToken } from '@/utils/auth'
import { isExternal } from '@/utils/validate'

const props = defineProps({
    modelValue: [String, Object, Array],
    // 图片数量限制
    limit: {
        type: Number,
        default: 5
    },
    // 大小限制(MB)
    fileSize: {
        type: Number,
        default: 5
    },
    // 文件类型, 例如['png', 'jpg', 'jpeg']
    fileType: {
        type: Array,
        default: () => ['png', 'jpg', 'jpeg']
    },
    // 是否显示提示
    isShowTip: {
        type: Boolean,
        default: true
    }
})

const { proxy } = getCurrentInstance()
const emit = defineEmits()
const number = ref(0)
const uploadList = ref([])
const dialogImageUrl = ref('')
const dialogVisible = ref(false)
const baseUrl = import.meta.env.VITE_APP_BASE_API
const uploadImgUrl = ref(import.meta.env.VITE_APP_BASE_API + '/common/upload') // 上传的图片服务器地址
const headers = ref({ Authorization: 'Bearer ' + getToken() })
const fileList = ref([])
const showTip = computed(
    () => props.isShowTip && (props.fileType || props.fileSize)
)

watch(
    () => props.modelValue,
    (val) => {
        if (val) {
            // 首先将值转为数组
            const list = Array.isArray(val) ? val : props.modelValue.split(',')
            // 然后将数组转为对象数组
            fileList.value = list.map((item) => {
                if (typeof item === 'string') {
                    if (item.indexOf(baseUrl) === -1 && !isExternal(item)) {
                        item = { name: baseUrl + item, url: baseUrl + item }
                    } else {
                        item = { name: item, url: item }
                    }
                }
                return item
            })
        } else {
            fileList.value = []
            return []
        }
    },
    { deep: true, immediate: true }
)

// 上传前loading加载
function handleBeforeUpload(file) {
    let isImg = false
    if (props.fileType.length) {
        let fileExtension = ''
        if (file.name.lastIndexOf('.') > -1) {
            fileExtension = file.name.slice(file.name.lastIndexOf('.') + 1)
        }
        isImg = props.fileType.some((type) => {
            if (file.type.indexOf(type) > -1) return true
            if (fileExtension && fileExtension.indexOf(type) > -1) return true
            return false
        })
    } else {
        isImg = file.type.indexOf('image') > -1
    }
    if (!isImg) {
        proxy.$modal.msgError(
            `文件格式不正确，请上传${props.fileType.join('/')}图片格式文件!`
        )
        return false
    }
    if (file.name.includes(',')) {
        proxy.$modal.msgError('文件名不正确，不能包含英文逗号!')
        return false
    }
    if (props.fileSize) {
        const isLt = file.size / 1024 / 1024 < props.fileSize
        if (!isLt) {
            proxy.$modal.msgError(
                `上传头像图片大小不能超过 ${props.fileSize} MB!`
            )
            return false
        }
    }
    proxy.$modal.loading('正在上传图片，请稍候...')
    number.value++
}

// 文件个数超出
function handleExceed() {
    proxy.$modal.msgError(`上传文件数量不能超过 ${props.limit} 个!`)
}

// 上传成功回调
function handleUploadSuccess(res, file) {
    if (res.code === 200) {
        uploadList.value.push({ name: res.fileName, url: res.url })
        uploadedSuccessfully()
    } else {
        number.value--
        proxy.$modal.closeLoading()
        proxy.$modal.msgError(res.msg)
        proxy.$refs.imageUpload.handleRemove(file)
        uploadedSuccessfully()
    }
}

// 删除图片
function handleDelete(file) {
    const findex = fileList.value.map((f) => f.name).indexOf(file.name)
    if (findex > -1 && uploadList.value.length === number.value) {
        fileList.value.splice(findex, 1)
        emit('update:modelValue', listToString(fileList.value))
        return false
    }
}

// 上传结束处理
function uploadedSuccessfully() {
    if (number.value > 0 && uploadList.value.length === number.value) {
        fileList.value = fileList.value
            .filter((f) => f.url !== undefined)
            .concat(uploadList.value)
        uploadList.value = []
        number.value = 0
        emit('update:modelValue', listToString(fileList.value))
        proxy.$modal.closeLoading()
    }
}

// 上传失败
function handleUploadError() {
    proxy.$modal.msgError('上传图片失败')
    proxy.$modal.closeLoading()
}

// 预览
function handlePictureCardPreview(file) {
    dialogImageUrl.value = proxy.$fullUrl(file.url)
    dialogVisible.value = true
}

// 对象转成指定字符串分隔
function listToString(list, separator) {
    let strs = ''
    separator = separator || ','
    for (let i in list) {
        if (undefined !== list[i].url && list[i].url.indexOf('blob:') !== 0) {
            strs += list[i].url.replace(baseUrl, '') + separator
        }
    }
    return strs != '' ? strs.substr(0, strs.length - 1) : ''
}
</script>

<style scoped lang="scss">
// .el-upload--picture-card 控制加号部分
:deep(.hide .el-upload--picture-card) {
    display: none;
}
</style>